Efficient biexciton (BX) photoluminescence (PL) from quantum dots (QDs) paves the way to the generation of entangled photons and related applications. However, the quantum yield (QY) of BX PL is much lower than that for single excitons (EX) due to efficient Auger‐like recombination. In the vicinity of plasmon nanoparticles, the recombination rates of EX and BX may be affected by the Purcell effect, fluorescence quenching, and the excitation rate enhancement. Here, the effect of the plasmon resonance spectral position on the EX and BX PL is experimentally studied in two cases: when the plasmon band overlaps with the excitation wavelength and when it coincides with the QDs PL band. In the first case, the EX and BX excitation efficiencies are significantly increased but the EX QY reduced. As a result, the BX‐to‐EX QY ratio is higher than 1 at plasmon–exciton systems separations shorter than 40 nm. In the second case, the radiative recombination rates are enhanced by several orders of magnitude, which led to an increase in BX QY over distances of up to 90 nm. Finally, these two effects are obtained in the same hybrid structure, with the resultant increase in both excitation efficiency and QY of BX PL.

中文翻译：

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光谱重叠和分离距离对等离激元纳米粒子的激子和双激子量子产率以及量子点的辐射和非辐射复合率的影响

来自量子点（QD）的高效双激子（BX）光致发光（PL）为纠缠光子的产生和相关应用铺平了道路。但是，由于有效的俄歇样重组，BX PL的量子产率（QY）远低于单激子（EX）。在等离激元纳米粒子附近，EX和BX的重组率可能受到Purcell效应，荧光猝灭和激发率增强的影响。这里，在两种情况下通过实验研究了等离振子共振光谱位置对EX和BX PL的影响：当等离激子带与激发波长重叠时以及当其与QDs PL频带重合时。在第一种情况下，EX和BX的激励效率显着提高，但EX QY降低。结果是，等离子体激子系统间隔小于40 nm时，BX与EX的QY比率高于1。在第二种情况下，辐射复合率提高了几个数量级，这导致BX QY在最高达90 nm的距离上增加。最后，在相同的混合结构中获得了这两种效果，从而提高了BX PL的激励效率和QY。